This invention relates to new and useful improvements in thermostats and temperature control devices and systems.
The conventional temperature control devices normally utilize one temperature control selector which can be set to a predetermined temperature setting in order to turn attached equipment on and off at one selected temperature range.
As an example, a furnace thermostat will control the operation of the thermostat between upper and lower limits only and no means are provided to control ancilliary equipment such as lights or to control the thermostat by means of timing devices.
Conventional thermostats do not include a clock or timer to actuate the thermostat control circuit at selected or pre-determined times and conventional temperature control devices normally can only control AC power operated equipment.
Another disadvantage of previously used temperature control devices is that they cannot be used to replace a conventional thermostatic control without modification to the control which, of course, adds to the cost and difficulty in installing one temperature control device for an existing thermostat. Furthermore, conventional temperature control devices are provided with a relatively small temperature differential control, usually 2.degree. F. to 3.degree. F.